From the Plastic Surgery Department, Hadassah University Medical Center.
Division of Plastic Surgery, Sunnybrook Health Sciences Center.
Plast Reconstr Surg. 2023 Sep 1;152(3):629-637. doi: 10.1097/PRS.0000000000010284. Epub 2023 Feb 14.
Orbital floor fracture defect size and inferior rectus (IR) rounding index are currently accepted indications for surgery to prevent late enophthalmos. The authors analyzed the positive predictive value (PPV) of these indications.
Twenty-eight patients with orbital floor fractures presenting without enophthalmos underwent Hertel exophthalmometry at presentation and at weeks 1, 2, 3, 6, 13, 26, and 52 or more after injury. Orbital defect size and IR rounding index were measured from computed tomographic scans, and PPVs of defects of 1.5 to 2 cm 2 or larger and IR rounding index of 1 or higher for enophthalmos (≥2 mm) were calculated.
Nineteen patients had isolated orbital floor fractures (group A), three had noncontinuous orbital floor and medial wall fractures (group B), and six had continuous orbital floor with medial wall fractures (group C). Mean follow-up time was 440 days. Of all patients, 20 had a defect size of 1.5 cm 2 or larger, 12 had a defect of 2.0 cm 2 or larger, and 13 had an IR rounding index of 1 or higher. Of the 28 patients, only one from group A and two from group C developed enophthalmos of 2 mm only. The PPVs of orbital floor defect size of 1.5 cm 2 or larger and 2 cm 2 or larger (groups A and B only) for late enophthalmos were 6.7% and 0%, respectively. The PPV of IR rounding index of 1 or higher for late enophthalmos (all groups) was 0%.
For patients with orbital floor fractures presenting without enophthalmos, defects of 1.5 cm 2 or larger and 2 cm 2 or larger, and IR rounding index of 1 or higher, are weakly predictive of late enophthalmos. Furthermore, patients who do not develop enophthalmos within 3 weeks of injury are unlikely to develop significant (>2 mm) late enophthalmos.
CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.
目前，眶底骨折缺损大小和下直肌（IR）圆钝指数被认为是预防迟发性眼球内陷的手术指征。作者分析了这些指征的阳性预测值（PPV）。
28 例无眼球内陷的眶底骨折患者在受伤时及伤后 1、2、3、6、13、26 周和 52 周或更长时间进行 Hertel 突眼度测量。通过计算机断层扫描测量眶缺损大小和 IR 圆钝指数，并计算缺损面积为 1.5 至 2cm 2 或更大，以及 IR 圆钝指数为 1 或更高的患者发生眼球内陷（≥2mm）的 PPV。
19 例患者为单纯眶底骨折（A 组），3 例为非连续性眶底和内侧壁骨折（B 组），6 例为连续性眶底伴内侧壁骨折（C 组）。平均随访时间为 440 天。所有患者中，20 例眶缺损面积为 1.5cm 2 或更大，12 例为 2.0cm 2 或更大，13 例 IR 圆钝指数为 1 或更高。在 28 例患者中，仅有 1 例 A 组和 2 例 C 组患者出现 2mm 仅有的眼球内陷。A 组和 B 组（仅这两组）眶底缺损面积为 1.5cm 2 或更大和 2cm 2 或更大的患者发生迟发性眼球内陷的 PPV 分别为 6.7%和 0%。所有患者的 IR 圆钝指数为 1 或更高的患者发生迟发性眼球内陷的 PPV 为 0%。
对于无眼球内陷的眶底骨折患者，缺损面积为 1.5cm 2 或更大和 2cm 2 或更大，以及 IR 圆钝指数为 1 或更高，提示有发生迟发性眼球内陷的可能性较低。此外，受伤后 3 周内未发生眼球内陷的患者不太可能发生明显（>2mm）的迟发性眼球内陷。
临床问题/证据水平：风险，III 级。
